Dow Agrosciences LLC

Corteva Agriscience LLC

Dow Global Technolgoies LLC

University of Michigan

Michigan State University

Jossian Oppenheimer

Xiaoyong Li

Matthias Stefan Ober

Ronald B Leng

James William Ringer

Shawn D Feist

Reetam Chakrabarti

Jason S Fisk

Siyu Tu

Mark Muehlfeld

Mark A Nitz

Robert S Bauman

Daniel Randolph Henton

Milton R Smith

Robert E Maleczka

Michael Gullo

Mark V M Emonds

Catherine A Menning

Mark E Ondari

Dmitrijs Sabasovs

Daniel R Henton

William Jack Kruper, Jr

James M Renga

Arkady L Krasovskiy

Kim Eric Arndt

David E Podhorez

Patrick S Hanley

Christopher W Derstine

Robert C Clouse

Jayachandran Devaraj

Amaruka Hazari

Chathurika R K Jayasundara

Justin A Alberts

Will Kruper

Hao Li

Mark Vm Emonds

Mark Emonds

James Renga

Kim Arndt

James W Ringer

The present disclosure concerns a method for preparing florasulam which involves treating a solution of 2,6-difluoroaniline in 1,2-propylene glycol with: a) sulfonyl chloride III and then b) a base to provide, after workup and isolation, florasulam (I) in yields of about 65-85%. The treatment of 2,6-difluoroaniline with sulfonyl chloride III and the base are conducted by controlled additions.

Method of preparation of florasulam

Improved methods for preparing chemical precursors to sulfonyl chloride III, which are important intermediates in the preparation of pyroxsulam herbicide, are provided. Also provided are compounds of Formula III, Formula VII, and IV, wherein Ris a C-Calkyl, X is Cl or OH, Y is halogen, OH, or OR, and Ris a C-Calkyl.

Preparation of sulfonamide herbicide process intermediates

Improved methods for preparing chemical precursors to sulfonyl chloride III, which are important intermediates in the preparation of pyroxsulam herbicide are provided. Specifically, these precursors are compounds of Formulas VII and/or VIII, and IX, wherein R is a C-Calkyl, Ris a C-Calkyl, X is Cl or OH, Y is halogen, OH, or OR, and Ris a C-Calkyl. 

Improved methods of synthesizing 6-aryl-4-aminopicolinates, such as arylalkyl and alkyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates and arylalkyl and alkyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates, are described herein. The improved methods include a direct Suzuki coupling step, which eliminates the protection/de-protection steps in the current chemical process, and therefore eliminates or reduces various raw materials, equipment and cycle time as well as modification of other process conditions including use of crude AP, use of ABA-diMe, and varying pH, catalyst concentration, solvent composition, and/or workup procedures. This includes synthesis of 2-aryl-6-aminopyrimidine-4-carboxylates.

Synthesis of 6-aryl-4-aminopicolinates and 2-aryl-6-aminopyrimidine-4-carboxylates by direct suzuki coupling

Methods for the borylation of aromatic compounds using cobalt catalysts are provided.

Methods for producing borylated arenes

The present disclosure describes a method of coupling a first compound to a second compound, the method comprising: providing the first compound having a fluorosulfonate substituent; providing the second compound comprising an alkene; and reacting the first compound and the second compound in a reaction mixture, the reaction mixture including a catalyst having at least one group 10 atom, the reaction mixture under conditions effective to couple the first compound to the second compound.

Method for coupling a first compound to a second compound

Methods for the selective borylation of arenes, including arenes substituted with an electron-withdrawing group (e.g., 1-chloro-3-fluoro-2-substituted benzenes) are provided. The methods can be used, in some embodiments, to efficiently and regioselectively prepare borylated arenes without the need for expensive cryogenic reaction conditions.

Improved methods of synthesizing 6-aryl-4-aminopicolinates, such as arylalkyl and alkyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates and arylalkyl and alkyl 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylates, are described herein. The improved methods include a direct Suzuki coupling step, which eliminates the protection/de-protection steps in the current chemical process, and therefore eliminates or reduces various raw materials, equipment and cycle time as well as modification of other process conditions including use of crude AP, use of ABA-diMe, and varying pH, catalyst concentration, solvent composition, and/or workup procedures. This invention was expanded to include synthesis of 2-aryl-6-aminopyrimidine-4-carboxylates.

Synthesis of 6-aryl-4-aminopicolinates and 2-aryl-6-aminopyrimidine-4-carboxylates by direct Suzuki coupling

Methods include formation of 4-chloro-2-fluoro-3-substituted-phenylboronic acid pinacol esters. The method comprises contacting a 1-chloro-3-fluoro-2-substituted benzene with an alkyl lithium to form a lithiated 1-chloro-3-fluoro-2-substituted benzene. The lithiated 1-chloro-3-fluoro-2-substituted benzene is contacted with an electrophilic boronic acid derivative to form a 4-chloro-2-fluoro-3-substituted-phenylboronate. The 4-chloro-2-fluoro-3-substituted-phenylboronate is reacted with an aqueous base to form a (4-chloro-2-fluoro-3-substituted-phenyl)trihydroxyborate. The (4-chloro-2-fluoro-3-substituted-phenyl)trihydroxyborate is reacted with an acid to form a 4 chloro-2-fluoro-3-substituted-phenylboronic acid. The 4-chloro-2-fluoro-3-substituted-phenylboronic acid is reacted with 2,3-dimethyl-2,3-butanediol to form 4-chloro-2-fluoro-3-substituted-phenylboronic acid pinacol esters . Methods of using 4-chloro-2-fluoro-3-substituted-phenylboronic acid pinacol esters to produce 6-(4-chloro-2-fluoro-3-substituted-phenyl)-4-aminopicolinates are also disclosed.

Methods of forming 4-chloro-2-fluoro-3-substituted-phenylboronic acid pinacol esters and methods of using the same

Methods of isolating a 4-chloro-2-fluoro-3-substituted-phenylboronate include adding carbon dioxide gas or carbon dioxide solid (dry ice) to a solution comprising a 4-chloro-2-fluoro-3-substituted-phenylboronate, an inert organic solvent, and at least one lithium salt to react the at least one lithium salt with the carbon dioxide gas or carbon dioxide solid (dry ice) and form a mixture comprising the 4-chloro-2-fluoro-3-substituted-phenylboronate, the inert organic solvent, and a precipitated solid. The precipitated solid may be removed from the mixture. Methods of using 4-chloro-2-fluoro-3-substituted-phenylboronates to produce methyl-4-amino-3-chloro-6-(4-chloro-2-fluoro-3-substituted-phenyl)pyridine-2-carboxylates are also disclosed. A 4-chloro-2-fluoro-3-substituted-phenylboronate produced by one of the methods of isolating a 4-chloro-2-fluoro-3-substituted-phenylboronate is also disclosed, wherein the 4-chloro-2-fluoro-3-substituted-phenylboronate may be obtained at a yield of greater than or equal to about 90%.

Methods of isolating (4-chloro-2-fluoro-3-substituted-phenyl)boronates and methods of using the same

Methods include formation of 4-chloro-2-fluoro-3-substituted-phenylboronic acid pinacol esters. The method comprises contacting a 1-chloro-3-fluoro-2-substituted benzene with an alkyl lithium to form a lithiated 1-chloro-3-fluoro-2-substituted benzene. The lithiated 1-chloro-3-fluoro-2-substituted benzene is contacted with an electrophilic boronic acid derivative to form a 4-chloro-2-fluoro-3-substituted-phenylboronate. The 4-chloro-2-fluoro-3-substituted-phenylboronate is reacted with an aqueous base to form a (4-chloro-2-fluoro-3-substituted-phenyl)trihydroxyborate. The (4-chloro-2-fluoro-3-substituted-phenyl)trihydroxyborate is reacted with an acid to form a 4 chloro-2-fluoro-3-substituted-phenylboronic acid. The 4-chloro-2-fluoro-3-substituted-phenylboronic acid is reacted with 2,3-dimethyl-2,3-butanediol to form 4-chloro-2-fluoro-3-substituted-phenylboronic acid pinacol esters. Methods of using 4-chloro-2-fluoro-3-substituted-phenylboronic acid pinacol esters to produce 6-(4-chloro-2-fluoro-3-substituted-phenyl)-4-aminopicolinates are also disclosed.

Provided herein are methods of isolating a 4-chloro-2-fluoro-3-substituted-phenylboronic acid. The method comprises contacting a mixture of water, a water-miscible organic solvent, and a 4-chloro-2-fluoro-3-substituted-phenylboronic acid with a salt to form a water-miscible organic solvent layer and a water layer. The 4-chloro-2-fluoro-3-substituted-phenylboronic acid is partitioned into the water-miscible organic solvent layer, which is separated from the water layer. Additional methods are disclosed, as is a 4-chloro-2-fluoro-3-substituted-phenylboronic acid produced by one of the methods, wherein the 4-chloro-2-fluoro-3-substituted-phenylboronic acid is obtained at a yield of greater than approximately 90%.

Methods of isolating 4-chloro-2-fluoro-3-substituted-phenylboronic acids

Methods of producing methyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylate. One method comprises adding methyl isobutyl ketone to an aqueous solution comprising 4-chloro-2-fluoro-3-methoxyphenyl-boronic acid to form an organic phase comprising the 4-chloro-2-fluoro-3-methoxyphenylboronic acid and an aqueous phase. The organic phase and the aqueous phase are separated. The 4-chloro-2-fluoro-3-methoxyphenylboronic acid is reacted with methyl 4-(acetylamino)-3,6-dichloropyridine-2-carboxylate in methyl isobutyl ketone to produce methyl 4-(acetylamino)-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylate, which is deacetylated to produce methyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylate.

Methods of producing methyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylate

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Midland, MI, United States of America

Jossian Oppenheimer